Converting List In List To Dictionary

I got a list like this: [['a','b','1','2']['c','d','3','4']] and I want to convert this list to dictionary something looks like this: { ('a','b'):('1','2'), ('c','d'):('3

Solution 1:

You can't have list as key, but tuple is possible. Also you don't need to slice on your list, but on the sublist.

You need the 2 first values sublist[:2] as key and the corresponding values is the sublist from index 2 sublist[2:]

new_dict = {}
for sublist in li:
    new_dict[tuple(sublist[:2])] = tuple(sublist[2:])

print(new_dict)  # {('a', 'b'): ('1', '2'), ('c', 'd'): ('3', '4')}

The same with dict comprehension

new_dict = {tuple(sublist[:2]): tuple(sublist[2:]) for sublist in li}
print(new_dict)  # {('a', 'b'): ('1', '2'), ('c', 'd'): ('3', '4')}

Solution 2:

li = [['a','b','1','2'],['c','d','3','4']]
new_dict = {}
foritemin li:
    new_dict[(item[0], item[1])] = (item[2], item[3])

Solution 3:

I would use list-comprehension following way:

lst = [['a','b','1','2']['c','d','3','4']]
dct = dict([(tuple(i[:2]),tuple(i[2:])) for i in lst])
print(dct)

or alternatively dict-comprehension:

dct = {tuple(i[:2]):tuple(i[2:]) for i in lst}

Output:

{('a', 'b'): ('1', '2'), ('c', 'd'): ('3', '4')}

Note that list slicing produce lists, which are mutable and can not be used as dict keys, so I use tuple to convert these to immutable tuples.

Solution 4:

You can do it with dict comprehension:

li = [
    ['a', 'b', '1', '2'],
    ['c', 'd', '3', '4'],
]

new_dict = {(i[0], i[1]): (i[2], i[3]) for i in li}

print(new_dict)


# result
{('a', 'b'): ('1', '2'), ('c', 'd'): ('3', '4')}